Yes that is a c-hub....The knuckles are attached to the c-hub with kingpin bolts so don't get that confused with a kingpin front end.

This is what a kingpin looks like.

The knuckle is one piece and is attached to the upper and lower arms with ball joints. The balls are an integral part of the knuckle.

This is an example of what a MBX/PBS front end looks like.

The arm ends have the balls attached kinda the opposite of the kingpin design.

Just a quick question since I saw this picture. In this picture, just below the knuckle, on the arm, is a block of plastic molded and sticking up. What is this for? My knuckle hits this block and is grinding it away, just want to make sure it's not important.

It looks almost like a stop to keep the wheels from turning past a certain point, but the knuckle barely hits it, and has shaved the top off.

Just a quick question since I saw this picture. In this picture, just below the knuckle, on the arm, is a block of plastic molded and sticking up. What is this for? My knuckle hits this block and is grinding it away, just want to make sure it's not important.

It looks almost like a stop to keep the wheels from turning past a certain point, but the knuckle barely hits it, and has shaved the top off.

It's a steering stop. It prevents the steering from going too far..

Yes you can shave em off and it will have minimal impact as long as your steering endpoints are set correctly. Actually you can gain extra steering due to eliminating this stop becasue the wheels can turn further.

Be careful though, if you grind it off and you do not set your endpoints well, you can overdrive the steering and lock it up or even break the knuckles.